We too redid our valances. In our case the valance held the mini blinds and the spring loaded curtain rod we added.
See here for some pics. My wife Cindy did all the sewing work, I was just the hanger guy.... I use wood and metal on the camper, she uses cloth, yarn and thread...
And we redid the wall paper boarder to better match the new look
To your question on if the plastic expanding anchors will hold a curtain rod. If the rod mount is on top of a wall stud, then you can screw right to the stud and not need the plastic anchors. If the rod mount is out in the open area of the wall and no studs, I do not think the plastic anchors will last for holding power. The wall board is only 1/8" luan plywood. Not very strong against pull out. The plastic expanding anchor I do not think will grip the 1/8" wall board correctly like it can on 1/2" thick home dry wall.
If you want to try the expanding anchors, suggest finding some thin wood, like old paneling that is 1/8" thick and do a test out in the open to see if if will hold.
Hope this helps
Current Sunlines: 2004 T310SR, 2004 T1950, 2004 T2475, 2007 T2499, 2004 T317SR
Prior Sunlines: 2004 T2499 - Fern Blue
2005 Ford F350 Lariat, 6.8L V10 W/ 4.10 rear axle, CC, Short Bed, SRW. Reese HP trunnion bar hitch W/ HP DC
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